sched: allow cpuacct stats to be reset

Currently the schedstats implementation does not allow the statistics
to be reset. This patch aims to allow that.

  echo 0 > cpuacct.usage

resets the usage. Any other value is not allowed and returns -EINVAL.

Signed-off-by: Dhaval Giani <dhaval@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Dhaval Giani 2008-02-29 10:02:44 +05:30 committed by Ingo Molnar
parent 32cd756a80
commit 0297b80339

View file

@ -8381,10 +8381,34 @@ static u64 cpuusage_read(struct cgroup *cgrp, struct cftype *cft)
return totalcpuusage;
}
static int cpuusage_write(struct cgroup *cgrp, struct cftype *cftype,
u64 reset)
{
struct cpuacct *ca = cgroup_ca(cgrp);
int err = 0;
int i;
if (reset) {
err = -EINVAL;
goto out;
}
for_each_possible_cpu(i) {
u64 *cpuusage = percpu_ptr(ca->cpuusage, i);
spin_lock_irq(&cpu_rq(i)->lock);
*cpuusage = 0;
spin_unlock_irq(&cpu_rq(i)->lock);
}
out:
return err;
}
static struct cftype files[] = {
{
.name = "usage",
.read_uint = cpuusage_read,
.write_uint = cpuusage_write,
},
};